Night Shift scheduling requires version iOS (9.3 or later) to have the feature, otherwise it’s the same on any iPhone, iPad, or iPod touch. Here’s how it works:

1 Open the ‘Settings’ app in iOS and go to “Display & Brightness”
2 Tap on the “Night Shift” option underneath the Brightness section
3 Now in the ‘Night Shift’ settings, flip the switch for “Scheduled” to the ON position
4 In the “From / To” section, choose “Sunset to Sunrise” (or set a custom schedule as well if desired)
5 Return back to the Night Shift screen, and, optionally but highly recommended, set the “Color Temperature” to the “More Warm” setting furthest on the right

6 Exit Settings and enjoy your automatic Night Shifting display
Now when sunset or sunrise comes, the iPhone / iPad display will automatically shift to be warmer, or back to the regular blue-light heavy display.